It seems necessary for the optional item, but I do not know where to put it even if I try to purchase. It will not be usable on a standalone basis, and it will cost a shipping fee, which is very unkind. I feel even malice.
Although it was easy to install on a drink holder, it is because of the long part of the arm, it will be pretty grazing. As a countermeasure, we are considering attaching a stay of reinforcement. The plastic part attached to the nut at the bottom of the arm was removed immediately at the time of installation. I think that there is no problem as nuts are left. I hope it is more cheap · · ·.